Precisely: why would it show on p2p? And why would a music file have a double extension? I mean I understand that, for example, torrent files have sometimes double-extensions: one is the actual file's extension and the other is the .torrent extension so that the application would recognise it as a torrent. A music file doesn't need to be recognised as an .html or .xml or anything to permit playback.
I've heard of music files that whenever you try to play them they would open these pages on the net so maybe that's what this file's extension is. In the worst case scenario, it could be some kind of malignant program.

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iMac G4 OSX 10.3.9
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LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

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